Electric call and alarm system



A1136 6, 1935. R. M. HOPKINS? ET AL ELECTRIC CALL AND ALARM SYSTEM FiledJan. 15, 1930 2 Sheets-Sheet 2 pin-i725.

s a m a a, m; M f m mmr A m m Jaw v a Pm S. &\ A .w vk (\w 7 5 an O owPatented Aug. 6, 1935 UNITED STATES PATENT OFFICE York, N. Y.,

assignors to American District Telegraph Company, New York, N. Y., acorporation of New Jersey Application January 13, 1930, Serial No.420,471

8 Claims.

This invention relates to call and alarm systems and to modifications ofthe system described in the Hopkins application Serial No. 410,718 filedNov. 30, 1929 for Alarm switches, and more particularly to unitary meansfor sounding holdup alarms and the like and for sounding electric callmeans, though it is noted that in some of the claims the invention isnot limited to alarms, or call means.

One object of the invention is to provide an apparatus or system of thiskind having push buttons, which when operated singly, selectively sounddifferent call means, and when operated in unison, sound an alarm.

Another object of the invention is to provide an improved switch devicefor a system of this kind.

Another object of the invention is to provide a system of this kindwhich has also supervisory means for supervising the alarm circuit.

Other objects of the invention are to improve generally the simplicityand efhciency of such switches and systems and to provide a switchdevice oi this kind which is reliable in operation, and economical tomanufacture.

Still other objects of the invention will appear as the descriptionproceeds; and while herein details of the invention are described andclaimed, the invention is not limited to these, since many and variouschanges may be made without departing from the scope oi the invention asclaimed in the broader claims.

The inventive features for the accomplishment of these and other objectsare shown herein in connection with improved alarm systems, each ofwhich, briefly stated, includes a plurality of switch devices orstations each comprising a pair of sets of insulated switch members,each set comprising an outer switch and an inner switch, and ush buttonsfor separately or simultaneously opcrating the sets.

Conductors connect a source of current and an alarm in a circuit withthe outer switches of both switch devices in a manner to render thealarm operative if both sets, and therefore, both outer switches of thesame device are operated. Conductors are also provided whereby a pair ofcall means are connected with the inner switches respectively in amanner to selectively operate the call means respectively when the innerswitches are operated.

A. suitable signal means with detent therefor, similar to that in saidapplication, is shown for indicating when both alarm switches have beenoperated.

While in this specification and claims we speak of the right, left, andfront of the switch devices and mention inner and outer members andswitches, call means and alarms, it is understood that we use thesewords for designation, and that they are to be construed broadly enoughto cover other relative arrangements or positions than as shown, andother translating means and operating devices, and in general the termsare to be given broad interpretation for the purposes of protection.

In the accompanying drawin s showing, by way of example, three of manypossible embodiments of the invention,

Fig. 1 is a plan of one form of the switch device;

Fig. 2 is a front elevation thereof;

Fig. 3 is a plan, partly in section, showing the switch assembly;

Fig, 4 is a fragmental longitudinal sectional view, partly in elevation,showing the switch assembly and signal means therefor;

Fig. 5 is a iragmental plan showing a position of the signal and detentmeans;

Fig. 6 is a diagram showing one form of circuit, a closed circuit;

Fig. 7 is a diagram showing another form of closed circuit;

Fig. 8 is a fragmental plan showing a switch assembly for open circuit;and

Fig. 9 is a diagram showing the circuit for J use with the assembly ofFig. 8.

As shown in Figs. 1 to 6 one form of our combined alarm and call systemcomprises one or more stations or switch devices or assemblies l0, l0each comprising a casing H (Fig. 1) having a front window l2 (Fig. 2),and a pair of openings l3 (Fig. 3) on opposite sides of the casing fromeach other slidably receiving stems I 4 of push buttons I5.

A block l8 (Fig, 4) mounted in the casing carries a pair of sets 19, 25of relatively insulated parallel spring plate members, said sets beingmounted on respectively opposite sides of said block.

Each of said sets comprises an outer normally closed switch 2i, 22between the members of which are opposed contacts 25 and an innernormally open switch 23, 2 5 between the members of which are opposedcontact lugs 25.

The inner member 22 of the outer switch and the outer member 23 of theinner switch are extended frontwardly beyond the lugs and other members,with the button stems engaging the extended outer-switch members 22.

A detent spring plate member 28 engages against the inner face of aninner long insulating strip 25-) which is disposed along the entireinner face or" the inner member 2G in the case of each inner switch,projects frontwardly beyond all of the other members and said member 28.

Short insulating strips 313 separate the respective members 29, 22 and23, 24; said long strips 29 are disposed between the contact members E iand 28, as indicated; and bolts 3! passing through all of strips, platesand the block secure them together.

An indicator plate 32 (Fig. 2) similar to that shown in saidapplication, having slots 33 slidably received on rivets S t 'on aninner face of the casing is provided with a normal panel 3%] and asecond panel 36 of white and red or other different colors, either ofwhich is adapted to register with windows 52 on sliding movement of theplate.

A pair of separated alined ledges 3'! (Fig. 3)

on the inner face of said signal plate are enleased by the detentmembers to disengage the "plate only when both detent members arepressed inward somewhat more than is shown in Fig. 5. A spring 38mounted on said block and pressing against the plate causes it to moveto show the second panel when the ledges 3? are thus disengaged,whereupon the said ledges move to position of the dotted lines of Fig. 4

to hold the detent members 28 inward as in' Fig. 5,'after the buttonsand members 24 have been released.

The casing H is provided with a key-hole 39 (Fig. 2) positioned toreceive a key All (Fig. l) in position to engage theedge 4! (Fig. 2) ofthe plate and restore it to normal position, to permit the detentmembers to return to the normal position 01"" Fig. 3.

As shown in Fig. 6, conductors 15, Q5, ll, 48, 69, 59 connect a sourceof current 5!, solenoids 52, a supervising resistance lamp 53 and saidswitch devices i9, iii in a normally closed series circuit, translatingmeans such as solenoids being between said lamp 53 and one pole 55 ofthe source and the switch devices being between the lamp and the otherpole 5: 6 of said source. The

solenoid E2 constitutes part of translating means 52A- including anormally open local circuit 52" in which is a signal or alarm means 52.When the solenoid is deenergized, the armature E3 closes by the actionof spring 55 upon contact 53", causing the alarm means to operate.

One member 2! of each normally closed switch of the device H3 or itbeing connectedto the adjacent part 58 or E9 respectively of. thecircuit toward the terminal 56 of the source, the other members 22 ofsuch switches of the respective devices lfl or it being connected to theadjacent part of the circuit #9 or 48 toward the lamp, whereby thecircuit is not opened unless both normally closed switches of the samedevice are opened. 7

One member 23 of each normally open switch is connected to the adjacentpart 39 or 8- of,

the circuit toward the lamp, whereby suchmemher is out on from theterminal 56 of the source, only when both of the normally closedswitches of a station are opened. Y r

1 Shunt conductors E2, 63 connect the. other member 24 of each normallyopen switch to the 5%,. are out 01f from the terminal 5%.

part 47 of the circuit between the alarms and the lamp; and translatingmeans such as call buzzers 54, B5 are interposed in said shuntconductors, whereby if one set of switch members E9 or 2B is actuated abuzzer will be actuated by current caused by the difference of potentialaround the lamp. However, if both sets 89 and 2&- are actuated, nobuzzer will be actuated, because the buzzers and the part of the circuitaway from the terminal 55 have been cut oil by the opening of both ofthe normally closed switches.

If desired a conductor 66 may be employed to connect members 24 ofdifferent stations to a single buzzer 6 as in Fig. 6, rather than havingthe buzzers all separately connected, as the buzz-- ers 65.

The lamp deserves, not only as a resistance as stated, but also as asupervisory meansffor the closed circuit. If this lamp goes out itindicates The operation of the switches and circuit of Figs. 1. to 6will be obvious from the foregoing. The one or more alarms 52-, whichmay be widely separated, operate through the instrumentality of a springiii to send an alarm only when no current passes through the wiring45-t'l; and

these alarms are held against operation by solenoids 52' when currentpasses, the passage of the normal current through the lamp lighting thislatter lamp and showing that the circuit is in order,

The stations or devices it, it are placed at different desks or indifierent oflices, and other locations, and if the person at suchlocation wishes to call a person at the buzzer M, the left hand buttonl5 of that station is pressed, permitting current to shunt the lampthrough conductors 5.13 or A9, unactuated members 2|, 22, conductor 4'!or Qlhactuated members 23 and 24 and conductors 62 or 6'5 and 62, til,53 and 45, without reducing or cutting oh the current through thesolenoids 52, whereby the alarm is not sounded but the buzzer E l issounded.

If it be desired to sound one of the buzzers 65, the associated righthand button of the associated station is pressed, sending currentthrough conductors Si? or 5% and Q9, unactuated 2!, 22, actuated members23, 24 and conductors E3, il, it and 55.

If it be desired to ring the alarmsbZ, both buttons l5 must be pressed.If both buttons of station iii be pressed current cannot pass fromconductor 58 and members 2! to members 22 i and conductor l because bothswitches 28, 22 have been opened. Therefore, the circuit is broken; nocurrent passes the solenoids 52, and the alarms will soundQ However,since the pressure of both buttons opens both switches 2|, 22 anddisconnects conductor it entirely from conductor 56, no current willpass the closed switches because these, being connected to the conductorThus no buzzer rings when both buttons of the station it are pressed.

In like manner, the alarms may be sounded by pressing both buttons ofstation it, without sounding the buzzers, since when both buttons ofstation i8 are not pressed, conductors t9 and 5% are connected as if oneconductor.

In the circuit of Fig. '7, the switch devices IE3, it" comprise each apair of sets of insulated switch members, as in Fig. 3, each set comprising a normally closed switch 2|, 22 and a normally open switch 23, 24.The button I5 serves as means for separately or simultaneously operatingthe sets, all as in Figs. 1 to 5. The alarms 52 are controlled bysolenoids 52 as in Fig. 6.

In the circuit of Fig. 7 a source of current 5|, solenoids 52, and theresistance 53 are all, by conductors 15, I6, 11, I8, I9, 80, connectedin a normally closed series circuit with the switch de vice, theresistance being between the solenoids 52' and the switch device, aninner member 22 of each outer switch and an outer member 23 of eachinner switch being connected to part of the conductor 80 (in station I)or I9 (in station I0) toward the source, and the other members 2| of thenormally closed switches being connected to the part I9 or I8 of thecircuit toward the resistance 53.

The buzzers 55 are connected by conductors 82 to the other members 24 ofthe normally open switches respectively and by conductors 83, 84 to thepart I5 of the circuit between the alarm and the source.

The operation of the normally closed circuit of Fig. 7 is similar tothat of Fig. 6; but in Fig. if both buttons I5 of station I0 be pressednot only is the main circuit broken, thus operating the alarm; but sincethe switch members 23 are connected to the conductor 80, current alsopasses through conductor 80, members 23, 24, conductors 82, 83, 84, andthe buzzer, but not through the solenoids 52. The operation of stationI0 of Fig. 7 is substantially the same as that of station I0 of Fig. 7.

If only one button be pressed, the closed circuit is not broken, butcurrent passes through a switch 23, 24 and sounds the buzzer as abovedescribed; but the buzzer shunt 82, 83, 84 will not shunt enough of thecurrent from the alarms to cause their operation, since the resistancelamp 85, interposed in the conductor 84, will prevent too much currentfrom shunting the alarms. Obviously the invention is not limited to anexterior resistance 85 in the shunt, as the buzzers may be wound forhigh resistance.

Figs. 8 and 9 show switch assemblies 90, 90, and a circuit designed tooperate on a normally open circuit. The switch assembly of Fig. 8comprises a block 88 similar to the block I8, and a pair of sets ofrelatively insulated parallel spring plate members,said sets beingmounted on respectively opposite sides of said block.

Each set comprises a pair of outer and inner normally open switcheswhich include members 9|, 92 and 93, 94 and these members carry contactswhich are like those shown at 25 and 26 in Fig. 3. In this case themembers 9| and 93 of the respective switches are extended frontwardlybeyond the shorter members, and the button stems I4 engage the extendedouter-switch members 9 I.

A long intermediate insulating strip 95 separates adjacent members 92,93, of adjacent switches and extends to the outer end of the extendedmember 93; and an inner insulating strip 96 along the entire inner faceof the inner member 94 of each inner switch. Each strip 96 projectsfrontwardly beyond its member 94 engages a detent spring plate member,as 28, and the latter is adapted to control and be controlled by thesignal plate, as 32.

Inwardly pointed pins 91, 98 fast on and projecting from the inner faceof the extended ends of the extended members SI, 93 are adapted toengage the insulating strips, whereby pressure of a button I5 closesboth associated switches.

Fig. 9 shows a normally open circuit for use with switch assemblies 90,90, as follows:

Conductors I00, IOI, I02 connect one terminal I03 of a source of currentI04 to one member 94 of each inner switch and also to the outer member Mof one (here the left hand) outer switch of each switch assembly.

Conductors 505, I06 connect the outer member of the other (here theright hand) outer switch of the assembly to one terminal IOl of the opencircuit alarms I08, the other terminal ID! of the alarms being connectedby a conductor I I0 to the other terminal III of the source I04.

Conductors H2, H4 connect the members 92 of associated outer switches,whereby pressure of both buttons of the same assembly causes current topass through conductors I00, I02, left hand members SI, 92, conductorH2, right hand members 92, 9I, conductor I05, the alarms and conductorIII to the source, thereby to cause an alarm.

When only a single button I5 is pressed, one switch SI, 92 is left open,the above circuit is not completed and no alarm sounds.

Conductors I22, I 23 connect the outer member 93 of each inner switch acommon conductor I20 connected through a resistance lamp I2I to theconductor H0 adjacent to the terminal III.

Call buzzers I24, I25 are interposed in said shunt conductors I22, I23respectively, whereby if any set of switch members 93, 94 is actuated abuzzer connected thereto will be actuated, the lamp I2! preventing thecomplete short circuiting of the alarms.

Somewhat in Fig. 6, there is provided a conductor IE8 (Fig. 9)connecting the left hand switch member 93 of station 99 to the conductorI22 between the buzzer I24 and the station 90. whereby the buzzer I24may be sounded from either station.

When a single button I5 is pressed current passes through conductorsI00, IOI, members 94, 93', conductor IE2 (or I23 or I26 and I22), abuzzer, conductor I20, lamp I2I to terminal III, thus sounding thebuzzer; but as only one button is pressed, the alarm is not sounded.

We claim as our invention:

1. An alarm system comprising a switch device having a pair of sets ofinsulated switch members, each set comprising a normally closed switchand a normally open switch; means whereby the sets may be separately orsimultaneously operated; a source of current, an alarm means responsiveto the opening of said closed circuit for operating said alarm, and aresistance lamp connected in a normally closed series circuit with theswitch device, the resistance being between the alarm and the switchdevice; one member of each normally closed switch being connected topart or" the circuit toward the source, the other member of the normallyclosed switches and one member of each normally open switch, beingconnected to the part of the circuit toward the resistance; and a callmeans connected between the other members of the normally open switchesrespectively and the part of the circuit between the alarm and the lamp.

2. An alarm system comprising in combination a plurality of switchdevices each including a pair of sets of insulated switch members, eachset comprising a normally closed switch and a normally open switch;movable means whereby the sets may be separately or simultaneouslyoperated; a source of current, an alarm means responsive to the openingof said closed circuit for operating said alarm,

and a resistance lamp connected in a normally circuit toward the source,the other member of the normally closed switches and one member of eachnormally open switch'being connected toa part of the circuit toward theresistance lamp; and a call means connected between the other members ofthe normally open switches respectively and the part of the circuitbetween the alarm and the resistance lamp.

3. In combination, a pair of translating means; a pair of operatingmeans for selectively operating said translating means respectively, theone to the exclusion of the other when the operating means are operatedseparately; additional translating means; and electrical means set inoperation by the simultaneous operation of both of the operating meansfor causing operation of the additional translating means, and at thesame time omitting operation of the first named pair of translatingmeans.

4. In combination, an alarm; a pair of call means; and means including apair of operating means for operating said call means respectively, theone call means to the exclusion of the other when only one operatingmeans is operated; and electrical means set in operation by thesimultaneous operation of both operating means for omitting operation ofeither call means and opcrating the alarm when by operation of theoperating means both operating means are operated.

5. An alarm and call system comprising in combination a plurality, ofswitch devices each comprising a pair of sets'of switch members, eachset comprising a normally closed alarm switch and a call switch; meansfor separately and simultaneously operating the sets; a source-ofcurrent; an alarm means adapted to send an alarm only when no currentpasses therethrough; conductors whereby said source and alarm means areconnected; in a closed circuit with the alarm switches, alarm switchesof the same switchdevice being in parallel with each other; a pluralityof call means; and conductors whereby the call means are connected inseries with the call switches respectively thereby to operate the callmeans respectively when the call switches are closed.

6. 'In combination, a pair of sets of switch members, each setcomprising a normally closed outer switch and a normally open innerswitch; means associated with each set for simultaneously opening thenormally closed switch and-closing the normally open switch; andyieldable indicator means held against operation by an inner switchwhenever either or both normally open switches are open, and releasedfor operation Whenever both normally open switches are closed.

7. In combination, a casing having a pair of openings on opposite sidesthereof; a block mounted in the casing; a pair of sets of relativelyinsulated spring members, the sets 'mountedgon opposite sides of theblock; each set comprising an outer normally closed switch and an innernormally open switch; each switch comprising an outer and inner contactmember; the inner mem ber of the outer switch and the outermember of theinner switch being extended 'frontwardly beyond the other outer switchmember; push buttons slidable in said openings and engaging the extendedouter switch members; an inner insulating strip disposed along the innerface of the inner member of each inner switch; a detent spring memberagainst the inner face ofeach inner strip and projecting frontwardly,and indicator means controlled 'by the detent members.

8. In combination, a casing having a pair of openings on opposite sidesthereof; a block mounted in the casing; a pair of setsof relativelyinsulated spring members, the setsmounted on opposite sides of theblock; each set'cornprising an outer normally closed switch and an innernorreally open switch; each switch comprising an outer and inner contactmember; the inner member of the outer switch and the outer member of theinner switch being extended frontwardly beyond the other outer switchmember; push buttons slidable in said openings and engaging the extendedouter switch members, whereby pressure on the push button-opens theouter switch and closes the innerswitch; a detent spring member againstthe inner face of each inner strip and projecting frontwardly, whereby.push 'button pressure is communicated through the outer and innermembers of the outer and inner switches to the detent spring; andindicator means controlled by the detent springs.

' RICHARD M. HOPKINS.

PAUL M. FARMER.

